Which class of fire involves ordinary combustibles?

Class A fires specifically involve ordinary combustibles, which include materials such as wood, paper, cloth, rubber, and many types of plastics. These materials are typically the most common fuels encountered in residential and commercial fires, making Class A fires the most prevalent categories firefighters deal with. The extinguishing method for Class A fires typically involves water, which cools the burning material and interrupts the combustion process.

In contrast, Class B fires involve flammable liquids and gases, such as gasoline or oil, requiring different extinguishing agents. Class C fires involve electrical equipment, with extinguishing methods focused on non-conducting agents to ensure safety. Class D fires consist of combustible metals and necessitate special extinguishing agents that are effective for those specific types of materials. Understanding these classifications helps firefighters determine the appropriate response and extinguishing techniques for various fire scenarios.